/* Root Variables */
:root {
    --primary-color: #2563eb;
    --primary-hover: #1d4ed8;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --background: #f8fafc;
    --surface: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--background);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

/* Navigation Bar */
.navbar {
    background: var(--surface);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.nav-menu a {
    color: var(--text-primary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 0.375rem;
    transition: background-color 0.2s;
}

.nav-menu a:hover, .nav-menu a.active {
    background-color: var(--background);
}

.nav-user {
    color: var(--text-secondary);
    font-weight: 500;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, #1d4ed8 100%);
    color: white;
    padding: 3rem 1rem;
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

/* Cards */
.card {
    background: var(--surface);
    border-radius: 0.5rem;
    padding: 1.5rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
}

.auth-card {
    max-width: 450px;
    margin: 2rem auto;
    background: var(--surface);
    padding: 2rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow-lg);
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.375rem;
    font-size: 1rem;
    transition: border-color 0.2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group small {
    display: block;
    margin-top: 0.25rem;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.375rem;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    transition: all 0.2s;
    text-align: center;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background-color: #475569;
}

.btn-danger {
    background-color: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-block {
    display: block;
    width: 100%;
}

/* Auction Grid */
.auction-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.auction-card {
    background: var(--surface);
    border-radius: 0.5rem;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.2s, box-shadow 0.2s;
    display: flex;
    flex-direction: column;
}

.auction-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.auction-card.closed {
    opacity: 0.8;
}

.auction-card.upcoming {
    border: 2px solid var(--warning-color);
}

.auction-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.no-image {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, #e2e8f0 0%, #cbd5e1 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary);
    font-weight: 500;
}

.auction-content {
    padding: 1.5rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.auction-content h3 {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.auction-content p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    flex: 1;
}

.auction-details {
    margin-top: auto;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
}

.detail-item {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
}

.detail-item .label {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.detail-item .value {
    font-weight: 500;
    color: var(--text-primary);
    font-size: 0.875rem;
}

.detail-item .value.highlight {
    color: var(--primary-color);
    font-weight: 600;
}

.detail-item .value.success {
    color: var(--success-color);
    font-weight: 600;
}

/* Badges */
.badge {
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
}

.badge-pending {
    background-color: #fef3c7;
    color: #92400e;
}

.badge-active {
    background-color: #d1fae5;
    color: #065f46;
}

.badge-closed {
    background-color: #e5e7eb;
    color: #374151;
}

.badge-admin {
    background-color: #dbeafe;
    color: #1e40af;
}

.badge-seller {
    background-color: #fce7f3;
    color: #9f1239;
}

.badge-buyer {
    background-color: #e0e7ff;
    color: #3730a3;
}

/* Banners */
.win-banner, .lose-banner, .upcoming-badge {
    margin-top: 1rem;
    padding: 0.75rem;
    border-radius: 0.375rem;
    text-align: center;
    font-weight: 600;
}

.win-banner {
    background-color: #d1fae5;
    color: #065f46;
}

.lose-banner {
    background-color: #fee2e2;
    color: #991b1b;
}

.upcoming-badge {
    background-color: #fef3c7;
    color: #92400e;
}

/* Tables */
.table-responsive {
    overflow-x: auto;
    margin-bottom: 2rem;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--surface);
    border-radius: 0.5rem;
    overflow: hidden;
    box-shadow: var(--shadow);
}

.data-table thead {
    background-color: var(--background);
}

.data-table th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    color: var(--text-primary);
    border-bottom: 2px solid var(--border-color);
}

.data-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.data-table tbody tr:last-child td {
    border-bottom: none;
}

.data-table tbody tr:hover {
    background-color: var(--background);
}

.data-table td.highlight {
    color: var(--primary-color);
    font-weight: 600;
}

.data-table td.success {
    color: var(--success-color);
    font-weight: 600;
}

/* Messages */
.error-message, .success-message {
    padding: 1rem;
    border-radius: 0.375rem;
    margin-bottom: 1.5rem;
}

.error-message {
    background-color: #fee2e2;
    color: #991b1b;
    border-left: 4px solid var(--danger-color);
}

.success-message {
    background-color: #d1fae5;
    color: #065f46;
    border-left: 4px solid var(--success-color);
}

.info-box {
    background-color: #dbeafe;
    color: #1e40af;
    padding: 1rem;
    border-radius: 0.375rem;
    margin-bottom: 1rem;
    border-left: 4px solid var(--primary-color);
}

/* Auth Links */
.auth-link {
    text-align: center;
    margin-top: 1.5rem;
    color: var(--text-secondary);
}

.auth-link a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.auth-link a:hover {
    text-decoration: underline;
}

/* Admin Dashboard */
.admin-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: linear-gradient(135deg, var(--primary-color) 0%, #1d4ed8 100%);
    color: white;
    padding: 1.5rem;
    border-radius: 0.5rem;
    box-shadow: var(--shadow);
}

.stat-card h3 {
    font-size: 0.875rem;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}

.stat-value {
    font-size: 2rem;
    font-weight: bold;
    margin: 0;
}

/* Dashboard Header */
.dashboard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.earnings-card {
    background: linear-gradient(135deg, var(--success-color) 0%, #059669 100%);
    color: white;
    padding: 1.5rem;
    border-radius: 0.5rem;
    text-align: center;
    min-width: 200px;
}

.earnings-card h3 {
    font-size: 0.875rem;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}

.earnings-amount {
    font-size: 2rem;
    font-weight: bold;
    margin: 0.5rem 0;
}

.earnings-card small {
    opacity: 0.8;
}

/* Section */
.section {
    margin-bottom: 3rem;
}

.section h2 {
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.empty-state {
    text-align: center;
    color: var(--text-secondary);
    padding: 3rem;
    background: var(--surface);
    border-radius: 0.5rem;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    overflow: auto;
}

.modal-content {
    background-color: var(--surface);
    margin: 5% auto;
    padding: 2rem;
    border-radius: 0.5rem;
    max-width: 500px;
    width: 90%;
    position: relative;
    box-shadow: var(--shadow-lg);
}

.close {
    color: var(--text-secondary);
    position: absolute;
    right: 1.5rem;
    top: 1rem;
    font-size: 2rem;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.2s;
}

.close:hover {
    color: var(--text-primary);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-container {
        flex-direction: column;
        align-items: stretch;
    }

    .nav-menu {
        justify-content: center;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .auction-grid {
        grid-template-columns: 1fr;
    }

    .admin-stats {
        grid-template-columns: 1fr;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .dashboard-header {
        flex-direction: column;
        align-items: stretch;
    }

    .earnings-card {
        width: 100%;
    }

    .data-table {
        font-size: 0.875rem;
    }

    .data-table th,
    .data-table td {
        padding: 0.75rem 0.5rem;
    }

    .modal-content {
        margin: 10% auto;
        width: 95%;
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    body {
        font-size: 0.875rem;
    }

    .container {
        padding: 1rem 0.5rem;
    }

    .hero {
        padding: 2rem 1rem;
    }

    .hero h1 {
        font-size: 1.5rem;
    }

    .btn {
        padding: 0.625rem 1.25rem;
        font-size: 0.875rem;
    }

    .btn-large {
        padding: 0.875rem 1.5rem;
        font-size: 1rem;
    }

    .auth-card {
        padding: 1.5rem;
    }

    .card {
        padding: 1rem;
    }

    .stat-value {
        font-size: 1.5rem;
    }

    .earnings-amount {
        font-size: 1.5rem;
    }
}

/* Print Styles */
@media print {
    .navbar, .hero, .btn, .modal {
        display: none !important;
    }

    body {
        background: white;
    }

    .container {
        max-width: 100%;
    }
}